Cyclidia rectificata

Saw them in hundreds roosting like monarchs on a tree branch hanging in the middle of a river. Do these moths also migrate or this is just a roosting behaviour after mass emergence? Have this behaviour been recorded before for this species? Kindly share any ref or links where I can read about this a little if you are aware of. Thanks!
SS: Cyclidia rectificata. I have seen mass emergences of Cyclidia, and also seen large congregations like this near Eaglenest. I have not seen any publications about this.